Sometimes they don't even need real evidence. In 10 years if they get their way, if the AI says you're guilty, you're guilty. Not to mention all the extrajudicial punishments like getting banned from having a bank account or a job, which is like a death sentence.
Municipal cameras do exist for speeding, tolls, and maybe other road research. But Flock is the definition of let's get everyone in dragnet surveillance so we can pick on whoever we want, at least try.